title: Hypoperfusion of brain parenchyma is associated with the severity of chronic cerebrospinal venous insufficiency in patients with multiple sclerosis: a cross-sectional preliminary report.
abstract: BACKGROUND
  Several studies have reported hypoperfusion of the brain parenchyma in multiple sclerosis (MS) patients. We hypothesized a possible relationship between abnormal perfusion in MS and hampered venous outflow at the extracranial level, a condition possibly associated with MS and known as chronic cerebrospinal venous insufficiency (CCSVI).
  
  
  METHODS
  We investigated the relationship between CCSVI and cerebral perfusion in 16 CCSVI MS patients and 8 age- and sex-matched healthy controls. Subjects were scanned in a 3-T scanner using dynamic susceptibility, contrast-enhanced, perfusion-weighted imaging. Cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were measured in the gray matter (GM), white matter (WM) and the subcortical GM (SGM). The severity of CCSVI was assessed according to the venous hemodynamic insufficiency severity score (VHISS) on the basis of the number of venous segments exhibiting flow abnormalities.
  
  
  RESULTS
  There was a significant association between increased VHISS and decreased CBF in the majority of examined regions of the brain parenchyma in MS patients. The most robust correlations were observed for GM and WM (r = -0.70 to -0.71, P < 0.002 and P corrected = 0.022), and for the putamen, thalamus, pulvinar nucleus of thalamus, globus pallidus and hippocampus (r = -0.59 to -0.71, P < 0.01 and P corrected < 0.05). No results for correlation between VHISS and CBV or MTT survived multiple comparison correction.
  
  
  CONCLUSIONS
  This pilot study is the first to report a significant relationship between the severity of CCSVI and hypoperfusion in the brain parenchyma. These preliminary findings should be confirmed in a larger cohort of MS patients to ensure that they generalize to the MS population as a whole. Reduced perfusion could contribute to the known mechanisms of virtual hypoxia in degenerated axons.
authors.affiliation: Vascular Diseases Center, University of Ferrara-Bellaria Neurosciences, Ferrara and Bologna, Italy. zmp@unife.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Zamboni
authors.forename: Erica
authors.initials: E
authors.lastname: Menegatti
authors.forename: Bianca
authors.initials: B
authors.lastname: Weinstock-Guttman
authors.forename: Michael G
authors.initials: MG
authors.lastname: Dwyer
authors.forename: Claudiu V
authors.initials: CV
authors.lastname: Schirda
authors.forename: Anna M
authors.initials: AM
authors.lastname: Malagoni
authors.forename: David
authors.initials: D
authors.lastname: Hojnacki
authors.forename: Cheryl
authors.initials: C
authors.lastname: Kennedy
authors.forename: Ellen
authors.initials: E
authors.lastname: Carl
authors.forename: Niels
authors.initials: N
authors.lastname: Bergsland
authors.forename: Christopher
authors.initials: C
authors.lastname: Magnano
authors.forename: Ilaria
authors.initials: I
authors.lastname: Bartolomei
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Salvi
authors.forename: Robert
authors.initials: R
authors.lastname: Zivadinov
mesh_terms: D000328:Adult; D000818:Animals; D001921:Brain / Q000098:blood supply* / Q000503:physiopathology*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications*; D012039:Regional Blood Flow; D014689:Venous Insufficiency / Q000150:complications*